Questions about exercise regimen. Is there any problems with doing workouts when hypo or hyperthyroid?

Not if treated . If your thyroid hormone levels are normal, there is no reason not to work out.
Worlout Hypo hyperth. While hypoth, your whole body system (brain+muscles-nerves) is too weak and you exhaust your system further. Hyper, heart rate pumps as you already exercise endlessly for weeks-months while you are resting, you aggravate your whole body much more. Both condition while not treated will lead to additional damage to the body. You surely ask in theory only i hope. Don't scare me!